One approach to an update of software (e.g., an operating system update) on a server computer involves an update controller copying the operating system from a first disk partition to a second disk partition. The update controller stores a copy of the operating system in a second disk partition. The update controller shuts down the server computer and reboots the server computer a first time to run the copy of the operating system from the second disk partition. After the first reboot, the update controller updates the operating system in the first disk partition. Next, the update controller shuts down the server computer and causes a second reboot of the server computer. After the second reboot, the server computer runs the updated operating system from the first disk partition.
One shortcoming of the approach is that during the time between the first shutdown and the second reboot, the client application services are disabled and the server computer is down causing a service outage and interruption. The service outage and interruption is typically between forty-five minutes and one hour. During the service outage and interruption commercially profitable services of the server computer are inoperable. A further shortcoming is that at least two shutdown and reboot cycles are required to complete the operating system update.
Another approach to the operating system update on the server computer involves a Solaris™ operating system update tool offered by Sun Microsystems, Inc. (Santa Clara, Calif. 95054, http://www.sun.com) under the trade identifier LiveUpdate. LiveUpdate copies the Solaris™ operating system stored in the first disk partition to the second disk partition. Then, LiveUpdate updates the copy of the Solaris™ operating system in the second disk partition. After the operating system is updated, the server computer runs the updated operating system from the second disk partition.
A shortcoming of this approach is that after the operating system is updated, the server computer runs the operating system from a different disk partition than before the update. It is undesirable to run the operating system from a different disk partition than before the update in complex telecommunication server computers. Running the operating system from the different disk partition than before the update adds complications when client applications attempt to access the telecommunication server computers. Yet another shortcoming is that if the server computer employs metadevices (e.g., logical devices representing one or more physical slices) to couple a file system to the disk partition, then the LiveUpdate tool is unable to update the contents of the disk partition.
Thus, a need exists for promotion of a decrease in a length of service outage of a server computer upon an update of software of the server computer.